Defect--impurity interactions in irradiated germanium

N-type samples of Ge containing approximately 2 to 5 x 1015 or 2 to 5 x 1016 P, As, Sb, or O4 clusters cm-3 were irradiated at approximately 3000K with thermal neutrons, and the apparent rate of removal of conduction electrons was determined as a consequence of lattice defects introduced by (n,γ) recoils. The rate of introduction of lattice defects was larger for P and As than for Sb-doped Ge, and increased slightly for Ge with a larger initial impurity concentration. There was no electrical evidence for multiple defect creation, or for any (VO) type defect state. However, the rate of introduction of lattice defects was less by a factor of three for n-type Ge in which the donor concentration was due to O4 clusters. Hiraki and Fukunaga [Defects in Semiconductors, (Reading, 1972) 335] suggested that the radiation resistance of Si or Ge p-n devices might be improved by the use of oxygen clusters to provide donors instead of conventional impurities, and these data are in general agreement with their observations. (U.S.)